Foam fire-extinguishing apparatus



Aug. 7, 1928.

W. GRAAFF FOAM FIRE EXTINGUISHING APPARATUS Filed Jan. 29, 1924 0! h /fl Press are Jive/2J0]:

Wm m4, 9

Patented Aug. 7,1928. UNITED STATES PATENT OFFICE.

WILHELH GBAAFI, OF BERLIN, GERMANY, ASSIGNORTO PYRENE-MTNIMAX CORPO- BATION, A. CORPORATION OF DELAWARE.

FOLK FIRE-EXTTNGUISHING APPARATUS.

Application filed January 29, 1924, Serial No. 689,383, and in Germany January 29, 1923.

The invention relates to an ap aratus for extinguishing fire by means 0 foam, in which the contents of a receptacle, which consists of the solution of a; salt, for ma stance a carbonate, is forced 1nto a second receptacle, which contains the reacting chemical and the foam generator. The displacement of the solution from the first receptacle is effected by water under pressure, which to is introduced into the first receptacle from the top by a pipe which extends almost down to its bottom. This first receptacle or reservoir is provided at its top with a recess into which the second receptacle fits in such a in manner that it may easily' be lifted out. When the contents of the first receptacle 1s driven into the second receptacle foam is produced in the latter, and the foam is then forced through a wide central extension into no a pipe leading to the fire. In order to prevent the discharge of pure water, which may cause damage, after the exhaustion of the chemicals producin the foam, 2. float is provided in the .secon receptacle in which the at production of the foam takes place, which tloat rises in correspondence with the llquid collecting in the receptacle and closes the outlet when the foam is exhausted and only liguid remains in the receptacle.- Thus no liquid tn can pass through the foam pipes. This float may also he employed when the contents of the first receptacle is forced into the second receptacle by a gaseous pressure medium. it will he understood that the utility of the at float is hy no means limited to apparatus in which the second receptacleis inserted in the hrst. The accompanying drawing illustrates an emhodiment of the invention.

liig. l is a vertical section through a foam producing apparatus and t Fig. Q is a vertical section on a smaller sccde through the enclosed or second receptac e.

Referring to the drawings a is a receptadill cle for a solution of carbonate or the like.

tor the reception of the receptacle cl. For.

conveying the liquid in the receptaclen into the receptacle d an elhow e is made'use of a which is-connected with the outlet branch f of the receptacle a by means of a cap nut g or the like, so as to be easily detachable. The receptacle d is divided into two compartments 2' and k by a perforated partition h. The compartment z contains the reacting chemical, for instance oxalic acid, for the chemical dissolved in the receptacle a, in the form of a powder and also the foam generator, for instance saponin, also in form of a powder. From the top of the compartment c' extends awide tube m with which is connected a hose or rigid pipe, not shown in the grawing, which conducts the foam to the Within the compartment 21 a float a is guided along a central rod 0. This float rests upon the bottom of the compartment 2' as long as the apparatus is not working and is embedded in the powdered chemicals contained therein. The specific gravity of the float is so calculated that it will float on the solution or on water but will not float on the foam produced in the second receptacle. When water finder ressure enters the receptacle a through t e ipe b it drives said solution in the receptac e before it through the outlet f and the elbow e, into the chamher k of the receptacle d. From here the solution passes through the perforations g in the partition 7 into the compartment 71 and there enters into reaction with the pow- .dered chemicals, so that foam is generated,

which is conducted out of the apparatus through the central tube m. In correspond ence with the collection of liquid in the compartment i the float n rises. When the compartment is entirely filled with liquid, the float assumes the position shown in Fig. 2 in broken lines, in which it closes the outlet of the tube at, so that no liquid can enter the latter or the foam pipe. In order to sheet the tight sealing of the tube m, the float a may preferahly be provided on its top with a suitable packing go either in the form of a ring or a disc.

What I claim as my invention and desire to secure by Letters Patent is In a foam fire extinguisher the combination of a receptacle containing a salt solution, a pipe for the admission of water under ressure extending from the top to near the ottom of said receptacle, a recess in the top of said receptacle, a second receptacle adapted to he inserted in said recess, an elhow pipe connecting the top of said first but all

llll

lilll) lllh the top of said extension, a float within said lower compartment and adapted to ascend along said rod and to seal the entrance to said extension, and an outlet pipe upon said extension.

In testimony whereof I afiix my signature.

WILHELM GRAAFF. 

